rendercheck is a set of simple tests of the X Render extension.  It is
designed for authors of Render implementations in X servers.

Tests currently include:
 * destination coordinates correctness
 * source coordinates correctness
 * transformed (FilterNearest) source coordinates correctness
 * composite with and without mask (with/without component alpha), with
   1x1 repeating pictures and 10x10 pictures
 * linear gradients
 * repeating sources/masks at POT and non-POT sizes
 * some regression tests for bugs from freedesktop.org bugzilla
